NEWARK, New Jersey (CNN) - If a running mate's chief role in a campaign is to play attack dog, then vice presidential prospect Joe Lieberman's audition is going swimmingly.

The Connecticut senator first questioned Barack Obama's patriotism and bipartisan record on Tuesday morning in Pennsylvania, saying the presidential contest is "between one candidate, John McCain who's always put the country first, worked across party lines to get things done, and one candidate who has not."

McCain's campaign later distributed those comments to reporters.

Lieberman, an Independent senator who caucuses with the Democratic Party, again sounded off to reporters on board McCain's campaign plane during a flight to New Jersey, praising the presumptive Republican nominee's record in the Senate and belittling Obama's.

"In the three and a half years Barack Obama has been in the senate with all respect, there is very little evidence of that kind of bipartisan outreach," said Lieberman.

"Barack Obama talks about bipartisanship," he continued. "John McCain has lived it, worked it, done it. That's why I think in the end, which is election day, which we hope is just the beginning, there are going to be many more Democrats who will vote for John McCain than Republicans who will vote for Barack Obama."

Faced with the V.P. question, Lieberman demurred.

Asked if he would accept a spot on the Republican ticket, he answered: "Uh, where?"

CNN=Politics Daily is The Best Political Podcast from The Best Political Team.

(CNN)—In the latest installment of CNN=Politics Daily, an international crisis has highlighted presumptive Republican presidential nominee John McCain’s foreign policy strengths. Could this be McCain’s moment? Senior Political Analyst Bill Schneider reports.

The Colorado-based group Focus on the Family released a controversial ad last month that called on Christians to “pray for rain” to drown out presumptive Democratic presidential nominee Barack Obama’s acceptance speech at the Denver convention. Internet reporter Abbi Tatton takes a look at the recent flood of criticism.

Plus: President Bush is struggling to keep the pressure on Russia, but McCain and Obama’s outspoken comments on the Russia/Georgia crisis are not making the diplomatic situation any less complicated. White House Correspondent Ed Henry has the story.

Finally: There are two categories that Obama’s VP contenders fall into – those that reinforce Obama’s message of “change” and those that counterbalance his perceived weaknesses. Jessica Yellin takes a look at the Illinois senator’s potential running mates and the groups into which they fall.

John Kerry's new ad, 'Fenway,' shows him giving Sean Bannon a purprle heart.

(CNN)— Massachusetts Senator John Kerry, facing his first Democratic primary challenger in 24 years, released his first campaign ad Tuesday spotlighting his record on veterans issues.

The 60-second spot, “Fenway,” tells the story of Iraq war veteran Sean Bannon, and how Kerry personally touched his life.

“I know how much he’s done for vets like me,” Bannon says of Kerry, praising Kerry’s record pushing for more funding for veterans’ mental health and education benefits, and his efforts on behalf of the move to boost the minimum death benefits for the families of military members from $12,000 to $250,000.

Kerry awarded Bannon his purple heart at Fenway Park on Patriots Day, and surprised him by being able to throw the first pitch of the game.

“John Kerry, he goes to bat for all us vets,” Bannon says.

The four-term senator and Vietnam veteran is being challenged in the September 16 primary by Massachusetts lawyer Ed O’Reilly.

Most recently, O’Reilly has challenged Kerry to a debate before their fall face-off.

Some critics say Kerry could face a more challenging re-election because of the decision to endorse Sen. Barack Obama for president over Sen. Hillary Clinton, who won his state’s Super Tuesday primary with 56 percent of the vote.

(CNN) – As House Republicans continue to focus on energy policy, Sen. Jim DeMint of South Carolina and Rep. Jeb Hensarling of Texas launched a new Web site Tuesday that highlights October 1 as the day the congressional ban on offshore oil drilling will end unless Congress takes some action to continue the ban.

The site prominently features a YouTube video clip of DeMint and Hensarling discussing energy policy and encouraging the public to contact their representatives in Congress about lifting ban on offshore oil drilling and oil shale recovery. The site also contains a clock-like widget counting down the time until October 1. Visitors to the site can copy the HTML code for the widget so that they can embed the countdown clock on their own blogs or Web sites. Visitors can also sign an online petition on the site and read a blog about energy policy.

The Heritage Foundation, a conservative think tank, also recently launched a Facebook application that allows users to add a gas-pump-shaped October 1 countdown clock to their profiles on the popular social networking site.

These online developments come on the heels of House Speaker Nancy Pelosi’s announcement Monday on Larry King Live that she would be open to holding a vote on offshore drilling if it were part of a larger energy package. Pelosi’s change in position echoes a similar change in position by Sen. Barack Obama, the presumptive Democratic presidential nominee. Since August 1, House Republicans have been staging a protest against Pelosi’s refusal to hold a vote on an energy bill before Congress’ five-week recess began.

ABOARD THE CNN ELECTION EXPRESS, ON I-80 IN OHIO (CNN) - The CNN Election Express is making its way across what could arguably be the considered the country’s most important battleground state.

Then-Texas Governor George W. Bush narrowly took Ohio eight years ago over Vice President Al Gore, and his two point victory four years ago over Senator John Kerry (D-Massachusetts) sealed the deal in his bid for re-election as president.

This time around both John McCain and Barack Obama are working overtime to win Ohio and its 20 electoral votes. Both candidates are making numerous swings through the state.

“I think that Ohio is going to be a battleground state. I have to campaign hard here. I have to work hard here,” said McCain while recently campaigning in the Buckeye State.

The most recent poll in the state shows it’s statistical dead heat between the candidates. The Quinnipiac survey, taken late last month, had Obama up by 2 points, well within the poll’s sampling error of 2.8 percent.

The CNN Election Express is on the road from DC to Denver, the site of the Democratic National Convention, making its way through some of the crucial battleground states that could decide the presidential election.

YORK, Pennsylvania (CNN) - Although Russia has apparently agreed to cease military action in Georgia, John McCain accused Moscow Tuesday of continuing to attack, saying that “possibly thousands” of civilians have been wounded or killed.

“President Medvedev stated that he has halted the offensive,” McCain said, “but reports indicate Russian military forces have continued attacks in some areas, and the situation remains fluid and dangerous.”

“Today the killing goes on, and the aggression goes on,” he said.

McCain spoke for seven minutes about the situation in Georgia at the beginning of a town hall meeting in Pennsylvania, praising the country’s “long and remarkable” history and its commitment to Western values. He said he spoke to Georgian president Mikhail Saakashvili earlier in the day.

Supporters want Hillary Clinton's name placed into nomination at the convention.

Some Hillary Clinton supporters want to make sure that the upcoming Democratic Convention doesn't turn into a "coronation" of Barack Obama.

A humorless organization called "The Denver Group" ran an ad in a Capitol Hill newspaper demanding that Hillary's name be placed in nomination at the convention and demanding that speeches be allowed in support of her nomination. They're just full of demands.

And if they don't get their way they are threatening a revolt. The ad says, "Will Howard Dean and the DNC turn the Democratic Party into the Boston Tea Party?"

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YORK, Pennsylvania (CNN) - John McCain used one of his largest and most ambitious town halls to date to brandish a pair of surrogates, Joe Lieberman and Tom Ridge, who may help him shore up support among independents in this fall battleground.

The Tuesday stop began with some campaign stunt work that turned the typically-mellow format into a lively Pennsylvania event that resembled one of the noisy rallies that characterized the Democratic primary.

The audience on hand - estimated by the campaign as north of 3,000 people - far exceeded the size of a standard McCain event. And the audience, who had been warmed up by a pair of television screens broadcasting a biographical film about the candidate, rose to their feet when McCain, Lieberman and Ridge arrived.

Sen. Hillary Clinton can win votes from delegates at the convention even if her name isn't placed in nomination.

WASHINGTON (CNN) - If Sen. Hillary Clinton's name is placed in nomination in Denver, Colorado, this year, it wouldn't be the first time that a candidate was beaten in the primaries and still formally contested the nomination at the convention.

But it would be the first time in the modern era of presidential primaries that a losing candidate has so visibly endorsed an opponent so many months before the convention, and then gone on to have his or her name placed in nomination.